1. Field of the Invention
The present application relates to a liquid crystal display device and, more particularly, to a liquid crystal display device and a fabrication method thereof.
2. Description of the Related Art
Display devices used in the past have typically been cathode-ray tubes (CRT). Presently, however, much effort has been made to study and develop various types of flat panel displays, such as liquid crystal display (LCD) devices, plasma display panels (PDP), field emission displays, and electro-luminescence displays (ELD), as substitutes for CRTs. Of these flat panel displays, LCD devices have advantages, such as high resolution, light weight, thin profile, compact size, and low power supply requirements.
An LCD device typically includes two substrates that are spaced apart and face each other with a liquid crystal material interposed between the two substrates. The two substrates include electrodes that face each other such that a voltage applied between the electrodes induces an electric field across the liquid crystal material. Alignment of the liquid crystal molecules in the liquid crystal material changes in accordance with the intensity of the induced electric field, thereby changing the light transmissivity of the LCD device. Thus, the LCD device displays images by varying the intensity of the induced electric field.
FIG. 1 is a schematic plan view of an LCD device according to the related art, and FIG. 2 is a cross-sectional view of an LCD device of FIG. 1.
As shown in FIGS. 1 and 2, the related art LCD device 1 includes a first substrate 11, a second substrate 61 and a liquid crystal layer 90 between the two substrates 11 and 61.
On the first substrate 11, a plurality of gate lines 13 and a plurality of data lines 30 cross each other to define a plurality of pixel regions P. A plurality of thin film transistors Tr are disposed at crossing portions of the gate and data lines 13 and 30. A pixel electrode 50 is connected to the thin film transistor Tr, in each pixel region P. The thin film transistor Tr includes a gate electrode 15, a semiconductor layer 23 having an active layer 23a and an ohmic contact layer 23b, a source electrode 33 and a drain electrode 35. A gate insulating layer 20 is disposed on the gate electrode 15, and a passivation layer 40 has a drain contact hole 43 exposing the drain electrode 35.
On the second substrate 61, a black matrix 63, including a first black matrix 63a and a second black matrix 63b are disposed. The first black matrix 63a has a lattice shape surrounding each pixel region P to shield the gate and data lines 13 and 30 and the thin film transistor Tr. The second black matrix 63b is disposed at a peripheral region of the second substrate 61 and is connected to end portions of the first black matrix 63a. 
A color filter pattern 66 including red (R), green (G) and blue (B) color filter patterns 66a, 66b and 66c fills openings of the first black matrix 63a and corresponds to each pixel region P. A common electrode 70 is disposed on the color filter pattern 66.
A spacer 56 is disposed between the first and second substrates 11 and 61 to maintain a cell gap.
A seal pattern 85 is disposed along the second black matrix 63b to surround a display region AA. The seal pattern 85 prevents leakage of the liquid crystal and attaches the first and second substrates 11 and 61.
A gate pad region GPA and a data pad region DPA are disposed at a non-display region that is outside the seal pattern 85 of the first substrate 11. In the gate and data pad regions GPA and DPA, gate and data pads are formed, respectively. The gate pad includes a gate pad electrode 12 and a gate pad electrode terminal 52. The data pad includes a data pad electrode (not shown) and a data pad electrode terminal 54. The data pad electrode may be made of the same material as the data line 30 in a process of forming the data line 30, and the data pad electrode terminal 54 is made of the same material as the pixel electrode 50 in a process of forming the pixel electrode 50.
The gate and data pads are connected to a PCB (printed circuit board) having driving circuits through a TCP (tape carrier package) film. A gate driver GD or a data driver is disposed on the TCP film.
A connection part 80 of an end portion of the TCP film contacts the gate or data pads i.e., the gate pad electrode terminal 52 or the data pad electrode terminal 54. A protecting film 87 covers the connection part 80. The protecting film 87 functions to prevent detachment of the TCP film and the gate and data pads.
In the related art LCD device, the seal pattern, the protecting film and the spacer are made of a heat-cured or UV-cured organic material including epoxy or acrylic. However, when such material is used, there are some problems. For example, when the seal pattern 85 is made of such material, breakdown of the seal pattern increases due to heating, and thus the drawbacks increase. In addition, epoxy and acrylic are expensive. Therefore, productivity decreases and product cost increases.